684421613 has 2 divisors, whose sum is σ = 684421614. Its totient is φ = 684421612.

The previous prime is 684421601. The next prime is 684421643. The reversal of 684421613 is 316124486.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 366263044 + 318158569 = 19138^2 + 17837^2 .

It is a cyclic number.

It is not a de Polignac number, because 684421613 - 2¹⁰ = 684420589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (684421643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342210806 + 342210807.

It is an arithmetic number, because the mean of its divisors is an integer number (342210807).

Almost surely, 2^684421613 is an apocalyptic number.

It is an amenable number.

684421613 is a deficient number, since it is larger than the sum of its proper divisors (1).

684421613 is an equidigital number, since it uses as much as digits as its factorization.

684421613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 35.

The square root of 684421613 is about 26161.4528075182. The cubic root of 684421613 is about 881.2678063032.

The spelling of 684421613 in words is "six hundred eighty-four million, four hundred twenty-one thousand, six hundred thirteen".